A wheeled walker, also called a rollator is in effect a walker with wheels. It combines a walking frame, the handles of which are usually adjustable in height, and is fitted with tire wheels so that rather than lifting the walker to move, the user just pushes it. Even early walkers were equipped with some mechanism for allowing the user to sit when desired; see U.S. Pat. No. 1,448,783 issued in 1921. Improvements have been made over the years including the ability to fold a walker, either down its center, as in U.S. Pat. Nos. 2,666,495 and 5,224,731 or in more modern versions by lifting the seat, and folding front to back, in U.S. Design Pat. No. 360,174, and in U.S. Pat. No. 5,865,065, particularly in FIG. 9 thereof. Examples of early frames, which in function are still used in the modern wheeled walkers, are found in U.S. Pat. Nos. 4,211,309 and in 4,341,381, the latter patent using the expedient of fixed wheels on the rear posts of the frame and casters on the front posts of the frame carrying wheels which are swiveled. A particularly relevant prior art rollator is depicted in FIG. 9 of U.S. Pat. No. 5,865,065 which describes the use of hand breaks that can be lifted to stop the wheeled walker momentarily or can be pushed downwardly to lock the wheeled walker in place.
The wheeled walker of U.S. Pat. No. 5,865,065 has certain dimensions which have been widely adopted in other walkers, although with some exceptions. As is typical of other wheeled walkers, it is equipped with a basket that lies beneath the seat, is at a height of 21½″, and uses 6″ wheels. Larger wheels, such as 8″ wheels, are much more desirable in that they provide a sturdier, more manuverable walker. It is also desirable to provide a lower seat, significantly lower than 21½″, but still accommodate the ability to place a full size basket so that it fits at least partially under the seat. Some available walkers do have 8″ wheels and do have lower seats but none have a combination thereof wherein a full size basket can be placed under the seat. For example, a variety of walkers are available at the web site www.scooterville.net which illustrate the variations obtainable. The “Traveler” 4900 shown at that site is a 3-wheel walker with 8″ wheels, though with no seat. The “Cruiser Deluxe Junior” has a seat height of only 18″, but with 6″ wheels. The “Mac” has 8″ wheels, but a 22″ seat height. The “Discovery” has 8″ wheels and a seat height between 20 and 22″.
A deficiency of the modern rollators is the strength of the baskets that are used with the rollator. The baskets are often hung from a section of the rollator and the mechanism for hanging, which is often simply a wire hook, is often not as strong as needed to preserve the structure and integrity of the basket. In addition, many of the units are noisy, particularly where the basket and seat comes in contact with its respective support structure. Most modern wheeled walkers also come with a back against which the user can lean. These are either straight as shown in FIG. 9 of U.S. Pat. No. 5,965,065 or deep as shown by the “Discovery” wheeled walker or “Voyager” wheeled walker at the Scooterville.net web site, or in U.S. Pat. No. 1,448,783. Typically, prior curved backs have a radius of curvature such that the depth of the rearmost point measured from the start of curvature (“rearmost depth”) is about 10 inches. If a line is drawn across the points of curvature of the opposing arms, the outside angle made with that line by a line drawn from the point of curvature to the center of the seat back (“arc angle”) is about 134 degrees.